Increase hdd size not vdi

[Stiffler]

Hi,

I am new to vbox,therefore when I started using I only gave 5gb to my system,now I am running out of space and need to give some more space. I could make the hard drive bigger if that would be .vdi,now I cant find any help on how to do it.Also tried switching hard drives,but then it does not boot. I really do not wanna start from fresh installation. Any tips would be appreciated.

[mpack]

Well, we seem to have established that it isn't a VDI, now all we need to establish is what it is.